society > communication > indication > that which identifies or distinguishes > personal identification > signature > sign [verb (reflexive)] (2)
transitive. With complement. reflexive. To sign oneself in the specified manner at the foot of a document; esp. as a formulaic valediction at the end…
transitive (reflexive). With complement. To affix a pseudonym, set of initials, etc., to a letter or work, in place of one's name.